1. Field of the Invention
The invention relates, generally, to a trolley assembly and, more particularly, to a roller of such an assembly.
2. Description of Related Art
In each of various manufacturing and warehouse facilities, such as those found in the food-processing or -service, materials-handling, and automotive industries, it is common practice to use a conveyor system that employs a trolley assembly for moving a load between spaced points within the facility. To this end, the trolley assembly typically includes a beam supported overhead. The beam defines an “I” cross-section to define a pair of spaced, identical, opposed, uniform tracks that are disposed parallel with each other. A pair of identical, substantially disc-shaped rollers are rollably guided on the respective tracks. Each of a pair of identical, uniform shafts is positioned within the respective roller such that a free end of the shaft projects horizontally out and is carried by the roller. A pair of identical hangers are carried by and depend downwardly from the free ends of the respective shafts. Each load is generally suspended from and carried by the hangers. In turn, each roller includes at least a housing and a bearing.
More specifically, the housing generally is solid steel and disk-shaped. The housing is also adapted for rolling engagement with a corresponding track and to house the entire bearing. The bearing generally is solid steel, cylindrical, hollow, and disposed within an interior of the housing and may have a rolling or ball element such that, during operation of the trolley assembly, as the housing rolls along the respective track, displacement of the housing relative to the bearing should take place.
The shaft is adapted to be press-fitted, slip-fitted, or otherwise matingly fitted within the bearing such that a free end of the shaft projects out and is carried by the housing. In this way, during operation of the trolley assembly, as the housing rolls along the respective track, the housing should rotate about the shaft, and no displacement of the bearing relative to the shaft should take place.
Each hanger generally is made of steel or other suitable material and includes a cylindrical upper portion defining an aperture therethrough for matingly receiving the free end of the respective shaft. A nut is tightened onto the free end of the shaft to clamp the upper portion between the nut and the housing. The hanger includes also a linear intermediate portion extending downwardly from the bottom of the upper portion such that the intermediate portions angle inwardly toward one another. The hanger includes also a linear lower portion extending downwardly from the bottom of the intermediate portion such that the lower portions are disposed spaced and parallel with each other. At least one carrier plate is sandwiched between and extends downwardly from the lower portions. The lower portions and at least one carrier plate are clampingly connected together by at least one bolt-and-nut combination. An aperture is defined through a free end of the at least one carrier plate for receipt thereby of a hook member or the like for use thereby in transporting the load.
A split half of a link of a conveyor chain is positioned in a notch defined in the lower portion of each hanger to embrace and drivingly engage the hanger. Powered movement of the chain in a known manner serves to move the trolley assembly along the track to move the load carried by the at least one carrier plate from point to point within the facility.
It should be appreciated by those having ordinary skill in the related art that the trolley assembly, in general, and roller thereof, in particular, just described are merely respective representative examples of a typical trolley assembly and roller thereof of the related art. It should be so appreciated also that each of such trolley assembly, in general, and roller thereof, in particular, can have any suitable structural design.
Although the trolley assembly of the related art moves the load from point to point within the warehousing or manufacturing facility, the roller tends to prematurely fail. More specifically, the cross-section defined by the housing can change with respect to that of the bearing via, for instance, the constant downward force applied by the load to the roller over time. This moment load can cause uneven wear of the bearing relative to the housing. Furthermore, the roller of the trolley assembly of the related art is not cost-effective to manufacture. In addition, the roller of the trolley assembly of the related art that is made of a material other than steel, e.g., plastic, can be structurally weak.
Moreover, in the food-processing or service industry, in particular, poultry trolley assemblies are used to move poultry between spaced points within a facility. In doing so, they are continually bombarded with high-pressure streams of water and/or solvents to clean the assemblies of unwanted poultry residue for health-safety reasons. In a heavy water environment such as this, the rollers need to be easier to clean and resistant to contamination and corrosion.
Thus, there is a need in the related art for a roller for a trolley assembly that does not tend to prematurely fail. More specifically, there is a need in the related art for a roller for a trolley assembly the housing of which does not unevenly wear with respect to the bearing during operation of the trolley assembly. There is a need in the related art for a roller for a trolley assembly that also is cost-effective to manufacture. There is a need in the related art for a roller for a trolley assembly that also is durable. There is a need in the related art for a roller for a trolley assembly that also is easier to clean and resistant to contamination and corrosion, especially for use in the food-processing or service industry.